Drying apparatus for pulverulent material



' P. SRIVE DRYING APFARATUS Fol! PULVERULENT MATERIAL 4 Sheets-Sheet Filed Dec. 29 1921 Fgti WW /%m P. SCRIVE DRYING APPARATUS FOR PULVERULENT MATERIAL L.. w: \m m l n m o M.. N W k ?ai W m W q .|J||; W o x W nm Vw P Jul 15, 1924. 1,50,4o

SCRIVE DRYING APPARATUS FOR PULVERULENT MATERIAL Filed Dec. 29 1921 4 Sheets-Sheet 4 Patented July 15,' `1924.

. UNITED STATES PAUL sonrvnor PARIS, FRANCE.

DRYING APPARATUS ro a PULVERULENT MATERIAL.

Application filed December 29,* 1921.

7 0 all 'whom it may cocer-n:

Be it known that I, PAUL SCRIVE, citizen of' the French Republic, residing at 33 .tue de la Tour, Paris, France, have invented certain new and useful Improvements in Drying Apparatus for Pulverulent Material, of which the following is a specification. 5

This invention has for its object improvements in rotary drying apparatuses, more particularly adapted for the treatment of pulverulent materials. These improvements are more' particularly characterized in that the rotary drum, having an inclined aXis and through which pass inreverse directions the hot gases and the material to be treated, is provided, on its outer wall, with apertures ;tor the re-entrance of the hot gases; these apertures open between inner longitudinal walls, in the shape of vanes, the outer faces of which are licked by the hot gases, whilst the inner faces `constitute buckets which are respectively fecl by overflowing of the material over their free inner edges. In these conditions, there is not only obtained a turning over of the material at each overflowng taking place between two successive inner buckets, but also, on the one hand, the less heated material is poured in the portion of the bucket the temperature of which is the higher, on the other hand, the hot gases are forced to pass through the screen formed by the material by passing from one of the buckets to the other.

In the accompanying drawing, given by way of example,

Figs. 1 and 1 show in vertical section two end portions of a single apparatus forming the subject matter o-f'the present invention.

Fig. 2 is a cross section taken on line 2-2 of Flg: 1, the dotted lines ndicating diagrammatically the interor form of the nasonry tunnel in which the drer' is arranged, r

Fig. 3 is a transverse section taken on line 3-3 of Fig. l the dotted lines indicating diagrammatically the interiorform of the masonry tunnel in which the drier is arranged.

Figs. 4 and 4 show in vertical section a modified form of the rotating drying. apparatus,

' line 6-6 of Fig. t

Serial No. 525,&98;

Fig'. 5 is an enlarged detail, partly in section of the pipe coupling of Fig. l, and

Fig. 6 is a transverse'section taken on the The dryng apparatus is essentially constituted by a casing ,a having' a po'lygonal base and capable of receiving a continuous rotary movement about its aXis of symmetry b 'which has' a certain inclinati'on from the horizontal.

This axs of symmetry is constituted by the aXis of a tubular shaft bthe ends of which, extending beyond the casing, are mounted in swvel bearings allowing slight fiexures. This shat't carries, moreover, the radial arms supporting the outer casing a, and the system of inner battle plates, as well as the bracing ensuring the rgiclity of the said casing. t

The radial arms (Fig. 2) form two central parallel groups (Fig. l) and are constituted by tubes c. These radial tubes which eXtend up to the apices of the polygon section of the drum a, are Secured, at their other ends, to the central shaft I), by means of collars d made in two 'pieces, embracing the said shaft and fitting against each other for enclosing in the half-sockets they carry, the ends of the said tubes c. On the other hand, they are connectedtogether on the outer casing a by means of connecting sleeves e ot' special shape, supporting longitudinal iron bars and through which pass the portion of the stay wires gparallel to the axis of rotation; Beyond the sectons containing the radi-al tubes 0, the stay wires g eXtend obliquely (Fig. 1) their ends being braced in the checks h carried by the central shaft.

The casing a is, on the other hand, connected'to its axis by arms c,constituted by fiat bar irons (Fig. 3) radially arranged. Each cross section of the drum a is provided with a number ofarms equal to half the number of the sides of the polygon-section. These arms k terminate at the corresponding apices, but the arms of a section are displaced relatively to those of the contiguous sections so as to' entirely surround the drum a. In ractice, the ends of these arms k are secure on the wall of the drying apparatus by means of castings 1 provided with-a se curing lug. At their central portion, they are curved in order to fiton the central hollow shaft b and they form a securing lug m which fits on the adjaeent arm.

The arms k and radial tubes 0 also carry, at a certain distance 'from the axis, an a ngle bar or a casting 'IL the free wing or supporting lug of which serves as a table for laying thereon fiat bar irons n parallel to the central shaft b and on which is secured the edge of a sheet iron plate 0 extending between the arms 76 or tubes 0 terminating at the same edge of the prismatic drum. This sheet-iron plate 0 forms one of the faces of a dihedral angle, the outer surface of which is formed by another sheet-iron plate n; these two plates eXtend over the entire length of the drum and the plate 0, riveted on the flat bars f and 'ni serves to connect the adjacent arms 0 together. The plates 0 are inclined toward the interior of the drum with respect to the surface of an imaginary prism limited to the areas passing through the points e and g; The sheet-iron plate 7) terminates at a certain distance of the adjacent edge by a raised edge q, so that it forms an opening r Situated above the adjacent oblique sheet-iron plate 0 and terminating at the corresponding edge of the prism. The edge Q of'the plate p is suitably reinforced by strips of metal which are attached at intervals to the plates 0 for the purpose of preventing 'distortion at the edge 'furnace whatever.

In the form of Construction illustrated in Figs. l, 2 and 3, the material to be dried is introduced through the tube h in the front portion of the drum, tha-t is to say in the highest portion, and it must travel through the said drum in order to be discharged through its lowest portion.

The products of the combustion cireulate in reverse direction and are drawn out of 'the drum by any type of aspirator s branched on the highest portion of the dry` mg apparatus.

The hot dry gases enter the drum a through the openings r provided in the faces of the latter, the hot dr gases being first in contact with the dampest materials near the charging end of the rotating drum.

The materials received in each of the V- shaped spaces formed between the sheetron plates o, 7), are progressively distributed, owlng to the rotation of the drum a, on the sheet-iron plate g, and by reason of the shape of the wall as formed by the durat1on of contact of the hot gases with the wall s prolonged. When the wall considered is inclined on the horizontal, the materals to be dried flow over the edge of the sheet-iron plate 0 and fall in the following y-shaped space which is formed by the adacent'portion of the wall 0 p, and coming at this moment above the same. hen the materials fall, they form a screen through which must pass the hot gases. Moreover, as the pouring goes on during a certain angular displacement of the drum a, it results therefrom that the materials which were nearest the pourng edge, are, when reaching the following sheet-iron plate, the most removed from the pouring edge limiting the latter. consequently, at each pouring or discharge level, the materials which were the less ventilated are, on the contrary, subjected to the most considerable ventilation, to which action of displacement is added that resulting from the fall of the materials in the stream of hot gases.

It is obvious that, simultaneously, the material travels along the aXis of the drum in order to reach the discharge orifice v The whole of these arrangements has the advantage of permitting manipulations of fragile materials without pulverizing them. Besides, the batling of the hot gases prevents the latter from directly passing around the axis b for issuing through the aspirator s, so that, owing to the forced contact of the dry and hot air with the material to' be dried, a very substantial amelioration of the calorific efiiciency is obtained.

The gyratory movement of the hot air caused by the walls of the buckets allows, inoreover, to obtain the following result:

This helical gyratory movement of the air passing on the materials before reaching the outlet and centralizing the damp air used towards the axis, on its way towards the end of the 'drying apparatus, allows a complete utilization of the air which is constantly renewcd up to its discharge outside the apparatus.

From this fact, the drying apparatus migl't be used, even if it did not receive any rotary movement about its axis.

In the example illustrated in Figs. 4, 5 and 6, the suction of the humidified gases takes place centrally through the hollow axis of the drum which is perforated with radial holes permitting the passage of the gascs and capable, moreover, of serving for the distribution of the materials to be dried, which enter within the hollow axisthrough its highest end, the lowest end being connected to an aspirator.

The tubular shaft b which, as previously mentioned, is inclined on the horizontal, is connected, at the highest end, to an inlet conduit t for the materials tobe treated, this conduit being nearlv vertical.

This connection can be effected by any known means, permitting the rotation of the shaft b, the conduit t being fixed, the finid tightness of the joint being ensured as well as possible.

The tubular shaft 7 is connected at its other end, to the eXhaust conduit ?fi for the damp gases by means similar to the previous ones.

The tubular shaft b is perforated with holes u in the portion of the said shaft eX- tending within the drying apparatus These holes are more numerous and of larger cross section at the highest end, so as to allow the easy fiowing away of the materials to be treated which are admitted through the vertical Conduit pipe t and fall in the hollow axis b; owing to the rotation of the latter, these materials spread out within thesaid hollow axis and fall, through the holes, in the buckets where they are treatecl as previously indicated.

The hot gases, introduced `at the lower part of the drying apparatus, through the openings v, travel within the drum as pre- Viously indicated and pass through the holes u which are less and less numerous and of smaller and smaller cross section towards the lowest end of the shaft b, so that the vacious circuits present the same resistance to the circulation of the gases. The shaft is connected to the Conduit pipe t on which is branched a suction apparatus permitting the circulation of the gas in the drum.

It has been set forth above that the gyratory movement of the hot air, caused by the walls of the buckets determines the centrali- Zation of the damp air towards the axis; the suction taking place through this axis, it results therefrom that the damp air only is sucked; the radial openings of the hollow axis being more numerous at the end where the feeding is effected, the ventilation is so much the more energetic as the treatment of the materials in less advanced, and reversely. These arrangements allow the most complete and rational utilization of the drying gases. i

hat I claim as my invention and desire to secure by Letters Patent is:

1. In a rotary drying apparatus having an inclined aXis for pulverulent materials, constituent elements of the drum composed of longitudinal buckets a drumconstituted by the assemblage of several of the said buckets, their concavity facing the aXis of the drum, these buekets being arranged in a geometrically similar manner relatively to the said axis, and providing between them equal intervals, means for securing thebuckets on the axis of the drum.

2. In a rotary drying apparatus having an inclined aXis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron plates forming a plane angle.

3.'In a rotary drying apparatus having an inclined axis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets bee ing each constituted 'by two sheet iron plates forming a plane angle, the arrangement of these buckets in such a manner that the apex of the plane angle coincides with the edge of. a prismatic surface having for' straight section a regular polygon.

et; In a rotary drying apparatus having an inclined aXis, for pulver-ulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron plates forming a 'plane angle, the arrangement of these buckets in such a manner that the apex of the plane angle coincides with the 'edge of 'a prismatic surface having for straight section a regular polygon, one of the faces of each plane angle coinciding with the corresponding face of the prismatic surface, but not completely covering the same, so as to provide an opening between the edge of the face of the plane angle and the apex of the following plane angle in the direction of rotation of the drum.

5. In a rotary drying apparatus having an 'inclined aXis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron plates forming a plane angle, the arrangement of these buckets in such a manner that the apeX` with i the of the plane angle coincides edge of a prismatic surface having for straight section a regular' polygon, one of the faces of each plane angle coinciding with the corresponding face of the prismatic surface, but not completely covering the* same, so as to provide an opening between the edge of the face of the plane angle and the apex of the following plane angle in the direction of rotation of the drum, the second face of each angle (the latextending up to the plane of symmetry passing through the axis of the drum and the apex of the preceding plane angle in' the direction of rotation. I 6.' In a rotary' drying apparatus having an inclined aXis, for pulverulent materials, constituent elements of thedrum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron' plates forming 'a plane angle, connecting sleeves secured to the apeX of each plane angle, in combinat-ion with radial tubes connecting them to collars secured on the aXis of the drum. i

7. In a rotary drying apparatus having an inclined aXis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron plates forming a plane angle, connecting sleeves secured to the apex of each plane angle, in combinaton with radial tubes conter being greater or at least equal to 'necting them to collars secured on the axis of the drum, radal arms having a securng member at the apeX of the corresponding plane angle, and a securing lug on the aXis of the drum.

8. In a rotary drying apparatus having an inclined aXis, 'for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, the said buckets being each constituted by two sheet iron plates forming a plane angle, connecting sleeves secured to the apex of each plane angle, in combination with radial tubes connecting them to collars secured on the aXis of the drum, radial arms having a securing member at the apex of the co rresponding plane angle, and a securing lug on the aXis of the drum, securing collars mounted on the radial tubes and connected to the inner faces of the plane angles, securing lugs mounted on the radial arms and connected to the inner faces of the plane angles.

9. In a rotary drying apparatus having an inclined axis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, a drum constituted by the assemblage of several of the said buckets, their concavity facing the axis of the drum, these buckets being arranged in a geometrieally similar manner relatively to the said axis, and providing between them 'equal intervals, the said buckets being each constituted by two sheet iron plates forming a plane angle, the arrangement of the inlet conduits forthe materials to be treated and of thelsuction 'conduits for the humidified gases at the same end of the drum, which is 'the highest end.

10. In a rotary drying apparatus having an inclined axis, for pulverulent materials, constituent elements of the drum, composed of longitudinal buckets, a drum constituted by the assemblage of several of the said buckets, their concavity faoing the axis of the drum, these buckets being arranged in geometrically similar manner relatively to the said axis, and providing between them equal intervals, the said buckets being each constituted by two sheet iron plates forming a plane angle, means permitting the central suction of the humidified gases.

11. Ina rotary d'ying apparatus having an inclined axis, for pulverulent materials, constituent elements of the drum composed of longitudinal buckets, a drum constituted by the assemblage of several of the said buckets, their concavity facing the axis of the drum, these buckets being arranged in a geometrically similar manner relatively to the said axis, and providing between them 'equal intervals, the said buckets being each constituted by two sheet iron plates forming a plane angle, an aXis of rotation 'for the drum, this aXis being hollow and radially perforated with holes the number and cross section of which decrease from the highest to the lowest end of the axis, means for connecting the lowest end of the hollow axis to a suction device.

12. In a rotary drying apparatus having an inclined axis, tor pulverulent materials, constituent elements of the drum composed of longitudinal buckets, a drum constituted by the assemblage of several of the said buckets, their concavity facing the aXis of the drum, these buckets being arranged in a geometrically similar manner relatively to the said axis, and providing between them equal intervals, the said buckets being each constituted by two sheet iron plates forming a plane angle, an aXis of rotation for the drum, this aXis being hollow and radially perforated with holes the number and cross section of which decrease from the highest to the lowest end of the axis, means for connecting the lowest end of the hollow axis to a suction device, means 'for connecting the highest end of the hollow axis to the inlet conduit :tor the materials to be treated.

13. In a rotary drying apparatus having an inclined aXis, for pulverulent materials, constituent elements of the drum composed of longitudnal buckets, a drum constituted by the assemblage of several of the said buekets, their concavit-y facing the aXis of the drum, these buckets being arranged in a geometrically similar manner relatively' to the said axis, and providing between them equal intervals, the said buckets being each constituted by two sheet iron plates forming a' plane angle, a crown terminating the hollow axis, a sleeve provided with frictional surfaces through which passes the aXis and Secured on the inlet conduit for the materials to be treated, this conduit entering within the hollow axis.

In testimony whereof I have aifixed my signature.

PAUL SCRIVE. A 

